Lubricating oil containing reaction product of certain acylated nitrogen containing intermediates and a boron compound



United States Patent 3, 538,832 LUBRICATING OIL CONTAINING REACTION PRODUCT OF CERTAIN ACYLATED NITRO- GEN CONTAINING INTERMEDIATES AND A BORON COMPOUND William M. Le Suer, Cleveland, Ohio, assignor to The Lubrizol Corporation, Wicklilfe, Ohio, a corporation of Ohio No Drawing. Original application Apr. 29, 1963, Ser. No. 276,214, now Patent No. 3,281,428, dated Oct. 25, 1966. Divided and this application Mar. 28, 1966, Ser. No. 537,675

7 Claims. (Cl. 252-475) This is a division of co-pending application Ser. No. 276,214, filed Apr. 29, 1963, now US. 3,281,428, which is a continuation-in-part of earlier filed application Ser. No. 132,305, filed Aug. 18, 1961, now US. 3,087,936.

This invention relates to oil-soluble nitrogenand boron-containing compositions and to the process of preparing the same. The compositions of this invention are useful as additives in lubricants, especially lubricants intended for use in internal combustion engines, gears, and power transmitting units.

One of the principal problems associated with present day automobile crankcase lubricants is that posed by the inevitable presence in the lubricant of foreign particles such as dirt, soot, water, and decomposition products resulting from breakdown of the lubricating oil. Even if there were none of this latter contaminant present the very nature of the design of the modern internal combustion engine is such that a significant amount of foreign matter will accumulate in the crankcase. Perhaps the most important of these contaminant-s is water because it seems to be responsible'for the deposition of a mayonnaise-like sludge. It appears that if there were no water present the solid components of the mayonnaise-like sludge would circulate with the oil and be removed. by the oil filter. It will be readily appreciated that the deposition of the sludge presents a serious problem with respect to the eflicient operation of the engine and that it is desirable to prevent such deposition of sludge-like material.

The presence of water and the precursors of sludge in a lubricating oil is dependent largely upon the operating temperature of the. oil. If the oil is operated at a high temperature the water, of course, will be eliminated by evaporation about as fast as it accumulates. In the absence of water as stated above the other foreign particles will be removed by the filter. At low oil temperatures, on the other hand, water will accumulate and so consequently will sludge. It is apparent that the environment in which a crankcase lubricant is maintained will determine to a large extent the ultimate performance of that lubricant.

High operating temperatures are characteristic of a lubricant in an engine that is run at relatively constant high speed. Thus, in an engine that is run at 60 miles per hour for a long period of time it is very unlikely that there will be any accumulation of water and it is similarly unlikely that there will be any formation and deposition of sludge, but in ordinary stop-and-go driving such as is the case with taxicabs, delivery trucks, police cruisers, etc., the crankcase lubricant will be alternately hot and cold, an ideal environment for the accumulation of water. In such cases the formation of sludge is a serious problem. This problem has been with the automotive industry for many years and its solution has been approached by the use of known detergents such as metal phenates and sulfonates but without notable success. Although such known detergents are very effective in solving the detergency problems associated with motor oils at high temperatures they have not been particularly effective in solving the problems associated with low temperature operation or, to put it better, those problems which are associated with crankcase lubricants in engines which are operated at alternating high and low temperatures.

It is accordingly a principal object of this invention provide novel compositions of matter.

It is also an object of this invention to provide compositions which are adapted for use as additives in hydrocarbon oils.

It is also an object of this invention to provide compositions which are efi'ective as detergents in lubricating compositions.

It is another object of this invention to provide a novel process for the preparation of products which are effective as dispersants in lubricant compositions.

It is another object of this invention to provide novel compositions which are effective dispersants in lubricant compositions intended for use in engines operated at alternating high and low temperatures.

It is another object of this invention to provide improved hydrocarbon oil compositions.

It is another object of this invention to provide improved lubricating compositions.

It is another object of this invention to provide improved fuel compositions.

These and other objects are achieved in accordance with this'invention by providing a process for preparing oil-soluble, nitrogenand boron-containing compositions comprising forming an acylated nitrogen intermediate by the reaction of a substantially hydrocarbon-substituted succinic acidproducing compound having at least about aliphatic carbon atoms in the substantially hydrocarbon-substituent with at least about one-half equivalent of an amido compound having the formula wherein R is selected from the class consisting of hydrogen and hydrocarbon radicals and R is selected from the class consisting of amino, cyano, carbamyl, and guanyl radicals and reacting said acylated nitrogen intermediate with a boron compound selected from the class consisting of boron oxide, boron halides, boron acids, ammonium salts of boron acids, and esters of boron acids in an amount to provide from about 0.1 atomic proportion of boron for each mole of said acylated nitrogen intermediate to about 10 atomic proportions of boron for each atomic proportion of nitrogen of said acylated nitrogen intermediate.

The substantially hydrocarbon-substituted succinic acid producing compounds from which the acylated nitrogen intermediates of the above process are derived are characterized by the presence within their molecular structure of a substantially hydrocarbon group having at least about 50 aliphatic carbon atoms and at least one succinic acidproducing group. They are illustrated by compounds having the structural formula 0 R-0H-d-X o CH;('l-X wherein R is a substantially hydrocarbon radical having at least about 50 aliphatic carbon atoms and X is a halogen, hydroxy, hydrocarbon-oxy, or acyloxy radical.

The substantially hydrocarbon substituent of the succinic acid-producing compound may contain polar groups provided, however, that the polar groups are not present in proportion-s sufiiciently large to alter significantly the hydrocarbon character of the substituent. The polar groups are exemplified by chloro, bromo, keto, ethereal, aldehydo,

and nitro, etc. The upper limit with respect to the proportion of such polar groups in the substituent is approximately based on the weight of the hydrocarbon portion of the substituent.

The sources of the substantially hydrocarbon substituent include principally the high molecular weight substantially saturated petroleum fractions and substantially saturated olefin polymers, particulraly polymers of mono-olefins having from 2. to 30 carbon atoms. The especially useful polymers are the polymers of l-mono-olefins such as ethylene, propcne, 1-butene,isobutene, l-hexene, loctene, 2-methyl-1-heptene, 3-cyclohexyl-l-butene, and 2-methyl- 5-propyl-l-hexene. Polymers of medial olefins, i.e., olefins in which the olefinic linkage is not at the terminal position, likewise are useful. They are illustrated by 2- butene, 3 pentene, and 4-octene.

Also useful are the interpolymers of the olefins such as those illustrated above with other interpolymerizable olefinic substances such as aromatic olefins, cyclic olefins, and polyolefins. Such interpolymers include, for example, those prepared by polymerizing isobutene with styrene; isobutene with butadiene; propene with isoprene; ethylene with piperylene; isobutene with chloroprene; isobutene with p-methyl styrene; l-hexene with 1,3-hexadiene; 1- octene with l-hexene; l-heptene with l-pentene; 3-methyll-butene with l-octene; 3,3-dimethyl-l-pentene with lhexene; isobutene with styrene and piperylene; etc.

The relative proportions of the mono-olefins to the other monomers in the interpolymers influence the stability and oil-solubility of the final products derived from such interpolymers. Thus, for reasons of oil-solubility and stability the interpolymers contemplated for use in this invention should be substantially aliphatic and substantially saturated, i.e., they should contain at least about 80%, preferably at least about 95%, on a weight basis of units derived from the aliphatic mono-olefins and no more than about 5% of olefinic linkages based on the total number of carbon-to-carbon covalent linkages. In most instances, the percentage of olefinic linkages should be less than about 2% of the total number of carbon-to-carbon covalent linkages.

Specific examples of such interpolymers include copolymer of 95% (by weight) of isobutene with 5% of styrene; terpolymer of 98% of isobutene with 1% of piperylene and 1% of chloroprene; terpolymer of 95% of isobutene with 2% of l-butene and 3% of l-hexene; terpolymer of 80% of isobutene with 20% of l-pentene and 20% of l-octene; copolymer of 80% of l-hexene and 20 of l-heptene; terpolymer of 90% of isobutene with 2% of cyclohexene and 8% of propene; and copolymer of 80% of ethylene and 20% of propene.

Another source of the substantially hydrocarbon radical comprises saturated aliphatic hydrocarbons such as highly refined high molecular weight white oils or synthetic alkanes such as are obtained by hydrogenation of high molecular weight olefin poylmers illustrated above or high molecular weight olefinic substances.

The use of olefin polymers having molecular weight of about 750-5000 is preferred. Higher molecular weight olefin polymers having molecular Weights from about 10,000 to about 100,000 or higher have been found to impart also viscosity index improving properties to the final products of this invention. The use of such higher molecular Weight olefin polymers often is desirable.

The substantially saturated, aliphatic hydrocarbon-substituted succinic acids and anhydrides are especially preferred for use as the acid-producing reactant of this process for reasons of the particular eifectiveness of the products obtained from such compounds as additives in hydrocarbon oils. The succinic compounds are readily available from the reaction of maleic anhydride with a high molecular weight olefin or a chlorinated hydrocarbon such as the olefin polymer described hereinabove. The reaction involves merely heating the two reactants at a temperature about -200 C. The product from such a reaction is an alkenyl succinic anhydride. The alkenyl group may be hydrogenated to an alkyl group. The anhydride may be hydrolyzed 'by treatment with water or steam to the corresponding acid. Either the anhydride or the acid may be converted to the corresponding acid halide or ester by reaction with, e.g., phosphorus halide, phenols, or alcohols.

In lieu of the olefins or chlorinated hydrocarbons, other hydrocarbons containing an activating polar substituent, i.e., a substituent which is capable of activating the hydrocarbon molecule in respect to reaction with maleic acid or anhydride, may be used in the above-illustrated reaction for preparing the succinic compounds. Such polar substituents may be illustrated by sulfide, disulfide, nitro, mercaptan, bromine, ketone, or aldehyde radicals. Examples of such polar-substituted hydrocarbons include polypropene sulfide, di-po'lyisobutene disulfide, nitrated mineral oil, di-polyethylene sulfide, brominated polyethylene, etc. Another method useful for preparing the succinic acids and anhydrides involves the reaction of itaconic acid with a high molecular weight olefin or a polar-substituted hydrocarbon at a temperature usually within the range from 100 C. to about 200 C.

The acid halides of the succinic acids can be prepared by the reaction of the acids or their anhydrides with a halogenation agent such as phosphorus tri-bromide, phosphorus pentachloride or thionyl chloride. The esters of such acids can be prepared simply by the reaction of the acids or their anhydrides with an alcohol or a phenolic compound such as methanol, ethanol, actadecanol, cyclohexanol, phenol, naphthol, octylphenol, etc. The esterification is usually promoted by the use of an alkaline catalyst such as sodium hydroxide or sodium alkoxide or an acidic catalyst such as sulfuric acid. The nature of the alcoholic or phenolic portion of the ester radical appears to have little influence on the utility of such ester as reactant in the process described hereinabove.

The amido compounds from which the acylated nitrogen intermediates of the process of this invention are derived have the structural formula H-N-R It wherein R is a hydrogen or hydrocarbon radical and R is selected from the class consisting of amino, cyano, oxycarbamyl, thiocarbamyl and guanyl radicals. It will be noted that because of the character of the R radical compounds of the above formula are not amines. They are referred to as amido compounds for the reason that they contain the radical. The R group of the formula is either hydrogen or a hydrocarbon radical having less than about 8 aliphatic carbon atoms such as an alkyl radical or an alkylphenyl radical in which the alkyl group is illustrated by methyl, ethyl, isopropyl, tertiary-butyl, n-pentyl, isooctyl, cyclohexyl, cyclopentyl, Z-methylcyclohexyl, or n-heptyl radical. The R radical may further be a 'phenyl-substituted alkyl radical such as 2-phenylethyl radical or 4-phenylbutyl radical.

The R radical of the above formula is illustrated by: amino radical (i.e., R N), cyano radical (i.e., NC), carbamyl radical (i.e., R NC(=X), wherein X is either oxygen or sulfur), or g'uanyl radical (R being as is defined previously). It will be noted that where R is an amino radical the amido compound is a hydrazine; where R is a cyano radical, the amido compound is a cyanamide; where the R radical is a carbamyl radical, the amido compound is a urea (or thiourea); and

where the R radical is a guanyl radical, the amido com- 1 pound is a guanidine.

Specific examples of the amido compounds include: hydrazine, phenylhydrazine, N,N-diphenylhydrazine, N,N'- diphenylhydrazine, N,N-dihexylhydrazine, cyanamide, dicyandiamide, dimethyl cy-anamide, diethyl cyanamide, diallyl cyanamide, diisopropyl cyanamide, dioctyl cyanamide, dioctyl cyanamide, urea, thiourea, N,N'-dimethylurea, N,N-dimethy1-urea, phenyl-urea, hexyl-urea, N,N-dioctyl-urea, phenyl-thiourea, N,N'-diphenyl-thiourea, guanidine, 1,1-dimethylguanidine, 1,3-dimethylguanidine, 2-cyclohexylguanidiine, l-aminoguanidine, l-cyanoguanidine, 1,2-dicyanoguanidine, biguanide, l-phenylbiguanide, l-cyclohexylbiguanide, l-(o-toluyl) bi guanide, etc.

The process of forming the acylated nitrogen intermediate by reacting the substantially hydrocarbon substituted succinic acid-producing compound with the amido compound is usually carried out by heating a mixture of the acid-producing compound and the amido compound at a temperature above about 80 C., preferably within the range from about 100 C. to about 250 C. However, when an acid or anhydr-ide is employed, the process often may be carried out at -a lower temperature such as room temperature. The use of a solvent such as benzene, toluene, naphtha, mineral oil, xylene, n-hex-ane, or the like is often desirable in the above process to facilitate the control of the reaction temperature.

The relative proportions of the acid-producing compound and the amido reactant to be used in the above process are such that at least about one-half of a stoichiometrically equivalent amount of the amido reactant is used for each equivalent of the acid-producing compound used. In this weight of the amido reactant is based upon the number of the nitrogen atoms. Similarly the equivalent weight of the acid-producing compound is based upon the number of the acid-producing radicals defined by the structural configuration Thus, urea has two equivalents per mole; amino guanidine has four equivalents per mole; a succinic acid or ester has two equivalents per mole, etc.

The upper limit of the useful amount of the amido reactant appears to be about 1 mole for each equivalent of the acid-producing compound used. On the other hand, the lower limit is about one-half equivalent of the amido reactant used for each equivalent of the acid-producing compound. In most instances, the preferred amount of the amido reactant is from about 1 to 3 equivalents for each equivalent of the acid-producing compound.

.The boron compounds useful in reaction with the acylated nitrogen intermediate include boron oxide, boron oxide hydrate, boron trifluoride, boron tribromide, boron trichloride, HBF boron acids such as boronic acid (e.g., alkylB(OH) or arylB(OH) boric acid, (i.e., H BO tetrabon'c acid (i.e., H B O metaboric acid (i.e., HBO ammonium salts of such boron acids, and esters of such boron acids. The use of complexes of a boron trihalide with ethers, organic acids, inorganic acids, or hydrocarbons is a convenient means of introducing the boron reactant into the reaction mixture. Such complexes are known and are exemplified by boron-trifluoride-diethyl ether, boronl tIifluoride-phenol, boron trifluoride-phosphoric acid, boron trichloride-chloroacetic acid, boron tribromide-dioxaneand boron tril'luoride-methyl ethyl ether.

Specific examples of boronic acids include methyl boronic acid, phenyl-boronic acid, cyclohexyl boronic acid, p-heptylphenyl boronic acid and dodecyl boronic acid.

The boron acid esters include especially mono-, di-, and tri-organic esters of boric acid with alcohols or phenols such as, e.g., methanol, ethanol, isopropanol, cyclohexanol, cyclopentanol, l-octanol, 2-octanol, dodecanol, be-

regard it will be noted that the equivalent henyl alcohol, oleyl alcohol, stearyl alcohol, benzyl alcohol, 2-butyl cyclohexanol, ethylene glycol, propylene glycol, trimethylene glycol, 1,3-butanediol, 2,4-hexanediol, 1, 2-cyclohexanedi0l, 1,3-octanediol, glycerol, pentaerythritol, diethylene glycol, carbitol, cellosolve, triethylene glycol, tripropylene glycol, phenol, naphthol, p-butylphenol, o,p-diheptylphenol, n-cyclohexylphenol, 2,2-bis-(p-hydroxyphenyl) propane, polyisobutene (molecular weight of 1500) -substituted phenol, ethylene chlorohydrin, ochlorophenol, m-nitrophenol, 6-bromo-octanol, m-nitrophenol, 6-bromo-octanol, and 7-keto-decanol. Lower alcohols, 1,2 glycols, and 1,3-glycols, i.e., those having less than about 8 carbon atoms are especially useful for preparing the boric acid esters for the purpose of this invention.

Methods for preparing the esters of boron acid are known and disclosed in the art (such as Chemical Revievv-s pages 9594064, volume 56). Thus, one method involves the reaction of boron trichloride with 3 moles of an alcohol or a phenol to result in a tri-organic borate. Another method involves the reaction of boric oxide with an alcohol or a phenol. Another method involves the direct esterification of tetra boric acid with 3 moles of an alcohol or a phenol. Still another method involves the direct esterification of boric acid with a glycol to form, e.g., a cyclic :alkylene borate.

The ammonium salts of boron acids include principally the salts of boric acid with ammonia or lower alkyl amines, i.e., mono-, di-, or tri-alkyl amines having less than 12 carbon atoms in each alkyl radical. Salts of ammonia or such amines with any other boron acid illustrated above are also useful. It is often desirable to use a mixture of an ammonium salt and at least a molar amount of water. Water tends to cause at least a partial hydrolysis of the salt so as to liberate a boron acid. Thus, the use of a mixture of an ammonium salt and water in many instances an expedient method of introducing a boron acid into the reaction mixture. Specific examples of the ammonium salts are ammonium salt of boric acid; a mixture of one mole of ammonium salt of boric acid and three moles of water; a mixture of one mole of monomethylamine salt of boric acid and one mole of Water; trimethylamine salt of boric acid; di-cyclo-hexylamine salt of boric acid, etc.

The reaction of the acylated nitrogen intermediate with the boron compounds can be eiTected simply by mixing the reactants at the desired temperature. The use of an inert solvent is optional although it is often desirable especially when a highly viscous or solid reactant is present in the reaction mixture. The inert solvent may be a hydrocarbon such as benzene, toluene, naphtha, cycle hexane, n-hexane, or mineral oil. The temperature of the reaction may be varied within wide ranges. Ordinarily it is preferably between about 50 C. and about 250 C. In some instances it may be 25 C. or even lower. The upper limit of the temperature is the decomposition point of the particular reaction mixture.

The reaction is usually complete'within a short period such as 0.5 to 6 hours. After the reaction is complete, the product may be dissolved in the solvent and the resulting solution purified by centrifugation or filtration if it appears to behazy or contain insoluble substances. Ordinarily the product is sufiiciently pure so that further purification is unnecessary or optional.

A desirable mode of carrying out the process for the preparation of the oil-soluble, nitrogenand boron-containing compositions consists in preparing a solution or slurry of the boron reactant such as boric acid in a hydrocarbon solvent such as mineral oil or toluene and adding the acylated nitrogen intermediate to this solution or slurry. The principal advantage of this particular method is the more efficient utilization of the boron reactant in the process. Another advantage is that the resulting mineral oil solution of the product is more readily filterable in the event that filtration becomes necessary to remove haze or insoluble contaminants. The yield of the desired prod net is often higher than that characteristic of the alternative methods of adding the boron reactant to the acylated nitrogen intermediate.

The reaction of the acylated nitrogen intermediate with the boron compounds results in a product containing boron and nitrogen. It is believed that the reaction results in the formation of a complex between boron and nitrogen. Such complex may involve in some instances more than one atomic proportion of boron with one atomic proportion of nitrogen and in other instances more than one atomic proportion of nitrogen with one atomic proportion of boron. The nature of the complex is not clearly understood. Evidence appears to indicate that the complex results from a direct linkage between boron and nitrogen and that in most instances, the radicals originally present on the boron and the nitrogen atoms do not take part directly in the complex formation. However, in the case of a bo-ron acid as the reactant, the reaction is often accompanied with the formation of water.

Inasmuch as the precise stoichiometry of the complex formation is not known, the relative proportions of the reactants to be used in the process are based primarily upon the consideration of utility of the products for the purposes of this invention. In this regard, useful products are obtained from reaction mixtures in which the reactants are present in relative proportions as to provide from about 0.1 atomic proportions of boron for each mole of the acylated nitrogen intermediate used to about atomic proportions of boron for each atomic proportion of nitrogen of said acylated nitrogen intermediate used. The preferred amounts of reactants are such as to provide from about 0.5 atomic proportion of boron for each mole of the acylated nitrogen intermediate to about 2 atomic proportions of boron for each atomic proportion of nitrogen used. To illustrate, the amount of a boron compound having one boron atom per molecule to be used with one mole of an acylated nitrogen intermediate having five nitrogen atoms per molecule is within the range from about 0.1 mole to about 50 moles, preferably from about 0.5 to about 10 moles.

The following examples are illustrative of the process for preparing the nitrogenand boron-containing compositions of this invention.

EXAMPLE 1 A polyisobutenyl succinic anhydride is prepared by the reaction of a chlorinated polyisobutene with maleic anhydride at 200 C. The polyisobutenyl radical has an average molecular weight of 850 and the resulting alkenyl succinic anhydride is found to have an acid number of 113 (corresponding to an equivalent weight of 500). To a mixture of 544 grams of this anhydride, 283 grams of mineral oil and 281 grams of toluene there is added 30 grams of urea at 45 C. The resulting mixture is heated at l30-l35 C. for 11 hours whereupon 2.5 cc. of water is distilled off. The residue is then heated to 140 C./ 20 mm. and filtered. The filtrate has a nitrogen content of 1%. A mixture of boric acid and the above filtrate in relative proportions such as to provide one atomic proportion of boron per atomic proportion of nitrogen is heated at 150 C. for 3 hours and filtered. The filtrate is found to have a boron content of 0.2%.

EXAMPLE 2 A mixture of this filtrate and boric acid in relative proportions such as to provide one atomic proportion of boron per atomic proportion of nitrogen is heated at C. for 3 hours and filtered at this temperature. The filtrate is an oil solution of the nitrogenand boron-containing composition having a nitrogen content of 4.1% and a boron content of 3.1%.

EXAMPLE 3 A product is obtained by the procedure of Example 1 except that urea is replaced with amino-guanidine on a nitrogen equivalent basis.

EXAMPLE 4 A product is obtained by the procedure of Example 1 except that urea is replaced with phenyl biguanide (i.e., C H NHC(=NH)NHC (=NH)NH on a nitrogen equivalent basis.

EXAMPLE 5 A product is obtained by the procedure of Example 1 except that urea is replaced with hydrazine hydrate on a nitrogen equivalent basis.

EXAMPLE 6 A product is obtained by the procedure of Example 1 except that urea is replaced with N,N-dibutyl thiourea on a nitrogen equivalent basis.

EXAMPLE 7 A product is obtained by the procedure of Example 1 except that urea is replaced with N,N'-diphenyl guanidine on a nitrogen equivalent basis.

EXAMPLE 8 A product is obtained by the procedure of Example 1 except that urea is replaced with 'guanyl-urea on a nitrogen equivalent basis.

EXAMPLE 9 A mixture of a polyisobutene (molecular weight of 1000) substituted succinic anhydride (555 grams, 1 equivalent) and guanide carbonate (60 grams, 2 equivalents) in 412 grams of mineral oil is heated at 150 C. for 6 hours and then blown with nitrogen at -180 C. for 3.5 hours. The residue is cooled to 100 C. and mixed with boric acid (107 grams, 5.2 equivalents). The resulting mixture is heated at 150 C. for 2 hours and C. for 1 hour and then filtered. The filtrate has a nitrogen content of 2.3% and a boron content of 1.4%.

The nitrogenand boron-containing products of this invention are useful for a wide variety of purposes including pesticides, plasticizers, rust-inhibiting agents for treatment of metals, corrosion-inhibiting agents, extreme pressure agents, anti-wear agents, and detergents.

A principal utility of such products is as additives in lubricants. It has been discovered in accordance with this invention that when used for such purpose the effectiveness of the nitrogenand boron-containing products to impart a specific property to a lubricant is closely related to the size of the substantially hydrocarbon substituent in the succinic radical of the acylated nitrogen composition from which such products are derived. More particularly it has been found that products in which the substantially hydrocarbon substituent contains more than about 50 aliphatic carbon atoms are effective to impart oxidation-inhibiting, corrosion-inhibiting, and detergent properties to a lubricant. It has also been found that the detergent properties of the products diminish sharply with a decrease in the size of the substantially hydrocarbon substituent having less than about 50 aliphatic carbon atoms so that products having less than about 35 aliphatic carbon atoms in this substituent are ineffective as detergent additives in lubricants.

The lubricating oils in which the compositions of this invention are useful as additives may be of synthetic, animal, vegetable, or mineral origin. Ordinarily mineral lubricating oils are preferred by reason of their availability, general excellence, and low cost. For certain applications, oils belonging to one of the other three groups may be preferred. For instance, synthetic polyester oils such as didodecyl adipate and di-2-ethylhexyl sebacate are often preferred as jet engine lubricants. Normally the lubricating oils preferred will be fluid oils, ranging in viscosity from about 40 Saybolt Universal Seconds at 100 F. to about 200 Saybolt Universal Seconds at 210 F.

The concentration of the nitrogenand boroncontaining compositions as additives in lubricants usually ranges from about 0.1% to about 10% by weight. The optimum concentrations for a particular application depend to a large measure upon the type of service to which the lubricants are to be subjected. Thus, for example, lubricants for use in gasoline internal combustion engines may contain from about 0.5 to about 5% of the additive, whereas lubricating compositions for use in gears and diesel engines may contain as much as or even more of the additive.

This invention contemplates also the presence of other additives in the lubricating compositions. Such additives include, for example, supplemental detergents of the ash containing type, viscosity index improviding agents, pour point depressing agents, anti-foam agents, extreme pressure agents, rust-inihibiting agents, and supplemental oxidation and corrosion-inhibiting agents.

The ash-containing detergents are exemplified by oilsoluble neutral and basic salts of alkali or alkaline earth metals with sulfonic acids, carboxylic acids, or organic phosphorus acids, or organic phosphorus acids characterized by at least one direct carbon-to-phosphorus linkage such as those prepared by the treatment of an olefin polymer (e.g., polyisobutene having a molecular Weight of 1000) with a phosphorizing agent such as phosphorus trichloride, phosphorus heptasulfide, phosphorus pentasulfide, phosphorus trichloride and sulfur, white phosphorus and a sulfur halide, or phosphorothioic chloride. The most commonly used salts of such acids are those of sodium, potassium, lithium, calcium, magnesium, strontium, and barium.

The term basic salt is used to designate the metal salts wherein the metal is present in stoichiometrically larger amounts than the organic acid radical. The commonly employed methods for preparing the basic salts involves heating a mineral oil solution of an acid with a stoichiometric excess of a metal neutralizing agent such as the metal oxide, hydroxide, carbonate, bicarbonate, or sulfide at a temperature about 50 C. and filtering the resulting mass. The use of -a promoter in the neutralization step to aid the incorporation of a large excess of metal likewise is known. Examples of compounds useful as the promoter include phenolic substances such as phenol, naphthol, alkylphenol, thiophenol, sulfurized alkylphenol, and condensation products of formaldehyde with a phenolic substance; alcohols such as methanol, 2-propanol, octyl alcohol, Cellosolve, Carbitol, ethylene glycol, stearyl alcohol, and cyclohexyl alcohol; amines such as aniline, phenylenediamine, phenothiazine, phenylbeta-naphthylamine, and dodecylamine. A particularly effective method for preparing the basic salts comprises mixing an acid with an excess of a basic alkaline earth metal neutralizing agent, a phenolic promoter compound, and a small amount of water and carbonating the mixture at an elevated temperature such as 60-200 C.

The preparation of a basic sulfonate detergent is illustrated as follows: A mixture of 490 parts (by weight) of a mineral oil, 110 parts of water, 61 parts of heptylphenol, 340 parts of barium mahogany sulfonate, and 227 parts of barium oxide is heated at 100 C. for 0.5 hour and then to 150 C. Carbon dioxide is then bubbled into the mixture until the mixture is substantially neutral. The mixture is filtered and the filtrate found to have a sulfate ash content of 25%.

The preparation of a basic barium salt of a phosphorus acid is illustrated as follows: A polyisobutene having a molecular weight of 50,000 is mixed with 10%by weight of phosphorus pentasulfide at 200 C. for 6 hours. The resulting product is hydrolyzed by treatment with steam C. to produce an acidic intermediate. The acidic intermediate is then converted to a basic salt by mixing with twice its volume of mineral oil, 2 moles of barium hydroxide and 0.7 mole of phenol and carbonating the mixture at 150 C. to produce a fluid product.

Furthermore, the oil-soluble, nitrogenand boron-containing compositions of this invention have the unique effectiveness in enhancing the extreme pressure and corrosion-inhibiting properties of a certain class of additives employed to impart these properties to a lubricant. More specifically, the additives which are so benefited are metal dithiocarbamates, Xanthates, the Group II metal phosphorodithioates and their epoxide adducts, hindered phenols, sulfurized cycloalkanes, di-alkyl polysulfides, sulfurized fatty esters, phosphosulfurized fatty esters, alka line earth metal salts of alkylated phenols, dialkyl phosphites, triaryl phosphites, and esters of phosphorodithioic acids.

The group II metal phosphorodithioates are the salts of acids having the formula in which R and R are substantially hydrocarbon radi cals. The metals for forming such salts are exemplified by barium, calcium, strontium, zinc, and cadmium. The barium and zinc phosphorodithioates are especially preferred. The substantially hydrocarbon radicals in the phosphorodithioic acid are preferably low or medium molecular Weightalkyl radicals and alkylphenyl radicals, i.e., those having from about 1 to about 30 carbon atoms in the alkyl group. Illustrative alkyl radicals include methyl, ethyl, isopropyl, isobutyl, n-butyl, sec-butyl, the various amyl alcohols, n-hexyl, methylisobutyl carbinyl, heptyl, 2-ethylhexyl, diisobutyl, isooctyl, nonyl, behenyl, decyl, etc. Illustrative lower alkylphenyl radicals include butylphenyl, amylphenyl, diamylphenyl, octylphenyl, etc. Cycloalkyl radicals likewise are useful and these include chiefly cyclohexyl and the lower alkylcyclohexyl radicals. Other substantially hydrocarbon radicals likewise are useful such as tetradecyl, octadecyl, eicosyl, butylnaphthyl, hexylnaphthyl, octylnaphthyl, cyclohexylphenyl, naphthenyl, etc. Many substituted hydrocarbon radicals may also be used, e.g., chloropentyl, dichlorophenyl, and dichlorodecyl.

The availability of the phosphorodithioic acids from which the Group II metal salts of this invention are prepared is well known. They are prepared by the reaction of phosphorus pentasulfide with an alcohol or phenol. The reaction involves four moles of the alcohol or phenol per mole of phosphorus pentasulfide, and may be carried out Within the temperature range from about 50 C. to about 200 C. Thus the preparation of 0,0-di-n-hexyl phosphorodithioic acid involves the reaction of phosphorus pentasulfide with four moles of n-hexyl alcohol at about C. for about 2 hours. Hydrogen sulfide is liberated and the residue is the defined acid. The preparation of the zinc or barium salt of this acid may be effected by reaction with zinc oxide or barium oxide. Simply mixing and heating these two reactants is sufficient to cause the reaction to take place and the resulting product is sutficiently pure for the purposes of this invention.

Especially useful Group II metal phosphorodithioates can be prepared from phosphorodithioic acids which in turn are prepared by the reaction of phosphorus pentasulfide with mixtures of alcohols. The use of such mixtures enables the utilization of cheaper alcohols which in themselves do not yield oil-soluble phosphorodithioic acids. Thus a mixture of isopropyl and hexyl alcohols can be used to produce a very effective, oil-soluble metal phosphorodithioate. For the same reason mixtures of simple phosphorodithioic (i.e., acids prepared from one alcohol) acids can be reacted with zinc oxide or barium oxide to produce less expensive, oil-soluble salts.

Another class of the phosphorothioate additives contemplated for use in the lubricating compositions of this invention comprises the adducts of the metal phosphorodithioates described above with an epoxide. The metal phosphorodithioates useful in preparing such adducts are for the most part the zinc phosphorodithioates. The epoxides may be alkylene oxides or arylalkylene oxides. The arylalkylene oxides are exemplified by styrene oxide, p-ethylstyrene oxide, alpha-methylstyrene oxide, 3-beta-naphthyl-1,3-butylene oxide, m-dodecylstyrene oxide, and pchlorostyrene oxide. The alkylene oxides include principally the lower alkylene oxides in which the alkylene radical contains 6 or less carbon atoms. Examples of such lower alkylene oxides are ethylene oxide, propylene oxide, 1,2-butene oxide, trimethylene oxide, tetramethylene oxide, butadiene monoepoxide, 1,2-hexene oxide, and propylene epichlorohydrin. Other expoxides useful herein include, for example, butyl 9,10-epoxy-stearate, epoxidized :soya bean oil, epoxidized tung oil, and epoxidized copolymer of styrene with butadiene.

The adduct may be obtained by simply mixing the phosphorodithioate and the epoxide. The reaction is usually exothermic and may be carried out within wide temperature limits from about C. to about 200 C. Because the reaction is exothermic it is best carried out by adding one reactant, usually the epoxide, in small increments to the other reactant in order to obtain convenient control of the temperature of the reaction. The reaction may be carried out in a solvent such as benzene, mineral oil, naphtha, or n-hexane.

The chemical structure of the adduct is not known. More than one mole, sometimes as many as four moles, of the epoxide can be made to combine with the phosphorodithioate to form products useful herein. However, adducts obtained by the reaction of one mole of the phos phorodithioate with from about 0.25 mole to about 1 mole of a lower alkylene oxide, particularly ethylene oxide and propylene oxide, have been found to be especially useful and therefore are preferred.

The hindered phenols are those in which the carbon atoms at both ortho positions to the phenolic group contain substituents so as to cause hinderence' of the phenolic group. The common substituents are the secondary and teriary alkyl radicals such as isopropyl, tert-butyl, tertpentyl, sec-pentyl, cyclohexyl, and tert-octyl radicals. They likewise may be aryl radicals or large polar radicals such as bromo or nitro radicals. Examples of the hindered phenols include 2,6-di-sec-butylphenol, 2,4-di-tert-butylphenol, 2,6-di-tert-oetyl-4-sec-pentylphenol, Z-tert-pentyl- 6 tert-hexylphenol, 2-tert-butyl-6-cyclohexy-6-heptylphe- 1101, 4,4 bis methylene-(2,6-di-tert-butylphenol), 4,4- methylene bis(2 tert-butyl-6-sec-butylphenol), 2,4-dimethyl 6-tert-butylphenol, 2,6-di-tert-butyl-6-methylphenol, and bis-(3,5-di-tert-butyl-4-hydroxybenzyl) sulfide.

The sulfurized esters of the fatty acids are obtained by the treatment of the esters with a sulfurizing agent such as sulfur or a sulfur halide, e.g., sulfur monochloride or sulfur dichloride. The esters are exemplified by methyl oleate, methyl stearate, allyl stearate, isopropyl myristate, cyclohexyl ester of tall oil acid, ethyl palmitate, isooctyl laurate, diester of ethylene glycol with stearic acid, tetraester of pentaerythritol with stearic acid, etc. Likewise useful are esters of higher alcohols or commercial alcohol mixtures such as octadecyl alcohol and sperm oil alcohol, and phenols such as phenol, naphthol, p-cresol, and o,pdihexylphenol. The sulfurization is effected most conveniently at temperatures between 100 C. and 250 C. More than one atom of sulfur can be incorporated into the ester by the use of an excess of the sulfurizing agent.

For the purpose of this invention sulfurized esters having as many as 4 or 5 atoms of sulfur per molecule have been found to be useful. Examples include sulfurized sperm oil having a sulfur content of 5%, sulfurized tall oil having a sulfur content of 9%, sulfurized methyl oleate having a sulfur content of 3%, and sulfurized stearyl stearate having a sulfur content of 15%.

Still another class of the fatty compounds consists of the phosphosulfurized fatty acid ester mentioned above. They are obtained by the treatment of the esters with a phosphorus sulfide, such as phosphorus pentasulfide, phosphorus sesquisulfide, or phosphorus heptasulfide. The treatment is illustrated by mixing an ester with from about 0.5% to 25% of a phosphorus sulfide at a temerature within the range from 100 C. to 250 C. The product contains both phosphorus and sulfur but the precise chemical constitution of such a product is not clearly understood. These and other methods for preparing the sulfurized esters and phosphosulfurized esters are known in the art.

The polysulfides include principally aliphatic and cyclo aliphatic disulfides, trisulfides, tetrasulfides, pentasulfides, or higher polysulfides. The term polysulfide designates a compound in which two substantially hydrocarbon radicals are joined to a group consisting of at least 2 sulfur atoms. It is represented for the most part by any of the structural formulas below:

wherein R and R are alkyl or cycloalkyl radicals and n is an integer usually less than 6. The nature of the linkage between the sulfur atoms is not clearly understood. It is believed, however, that such linkage may be described by a single covalent bond, a double bond, or a coordinate covalent bond. The polysulfides containing at least about 6 carbon atoms per molecule have greater oil-solubility and are generally preferred. Specific examples of such polysulfides are diisobutyl trisulfide, diisopentyl trisulfide, di-n-butyl tetrasulfide, dicyclopentyl disulfide, di-methylcyclohexyl tetrasulfide, di-Z-ethylhexylpentyl disulfide, dipentyl trisulfide, di-beta-pinyl pentasulfide, cyclohexyl cyclopentyl trisulfide, diparaffin wax trisulfide, di-terpenyl disulfide, didodecyl trisulfide, dibehenyl trisulfide, and diisobutyl hexasulfide. Other polysulfides, including polar-substituted sulfides, are exemplified by di(omega-bromopentyl)trisulfide.

The preparation of the polysulfide may be accomplished by any of the various processes which are known and disclosed in the art including, for example, the reaction of a chlorohydrocarbon with an alkaline metal polysulfide, the reaction of a mercaptan with sulfur and/or sulfur halide, the reaction of saturated and unsaturated hydrocarbons with sulfur and/ or sulfur halides, the reaction of a hydrocarbon monosulfide with sulfur, etc.

The phosphites useful herein are the diand tri-hydrocarbon esters of phosphorus acid. Examples of the phos phites are: dibutyl phosphite, diheptylphosphite, dicyclohexylphosphite, tri-(pentylphenyl)phosphite, tris-(dipentylphenyl) phosphite, didecyl' phosphite, di-stearyl phosphite, tris-(hexa-propylene-substituted phenyl)phosphite, tri-hexyl phosphite, di-heptyl phenyl phosphite, and tri (m-chloro-p-heptylphenyl phosphite.

The alkaline earth metal salts of the alkylated phenols include principally the salts of magnesium, barium, calcium, and strontium with phenolic substances containing an alkyl substituent having at least about 7 carbon atoms. The phenols are exemplified by alkyl phenols, alkyl naphthols, sulfurized alkyl phenols, and the condensation products of alkyl phenols with an aldehyde. Specific examples include magnesium 'octylphenate, barium polypropylene-substituted phenate in which the polypropylene substituent has a molecular Weight of 500, calcium salt of v alpha-dodecyl-beta-naphthyl, barium .salt of bis(heptylcalcium salt of the condensation product of two moles of heptylphenol with formaldehyde, barium dodecylphenate,

and strontium polyisobutene-substituted phenate in which the polyisobutene substituent has a moleculuar Weight of 350.

The esters of the phosphorodithioic acids include the aryl and the alkyl esters of the phosphorodithioic acids described hereinabove. A particularly useful group of the ester is obtained by the addition of the phosphorodithioic acids to an olefinic compound such as an alkene or an aralkene. They are obtained, for example, by the addition of diisopropylphosphorodithioic acid with styrene, propene, isobutene, cyclohexene, l-octene, methyl cyclohexene, isoprene, butadien'e, dipentene, or the like.

The following examples are illustrative of the lubricating compositions of this invention: (all percentages are by Weight).

Example I SAE 20 mineral lubricating oil containing 0.5% of the product of Example 1.

Example 11 SAE 30 mineral lubricating oil containing 0.75% of the product of Example 2 and 0.1% of phosphorus as the barium salt of di-n-nonylphosphorodithioic acid.

Example III SAE 10W-30 mineral lubricating oil containing 0.4% of the product of Example 3.

Example IV SAE 90 mineral lubricating oil containing 0.1% of the product of Example 4 and 0.15% of the zinc salt of an equimolar mixture of di-cyclohexylphosphorodithioic acid and di-isbutyl phosphorodithioic acid.

Example V SAE 30 mineral lubricating oil containing 2% of the product of Example 4.

Example VI SAE 20W-30 mineral lubricating oil containing of the product of Example 2.

Example VII SAE W-30 mineral lubricating oil containing 1.5% of the product of Example 5 and 0.05% of phosphorus as the zinc salt of a phosphorodithioic acid prepared by the reaction of phosphorus pentasulfide with a mixture of 60% (mole) of p-butylphenol and 40% (mole) of npentyl alcohol.

Example VIII SAE 50 mineral lubricating oil containing 3% of the product of Example 5 and 0.1% of phosphorus as the calcium salt of di-hexylphosphorodithioate.

Example IX SAE 10W-30 mineral lubricating oil containing 2% of the product of Example 4, 0.06% of phosphorus as zinc di-n-octylphosphorodithioate, and 1% of sulfate ash as barium mahogany sulfonate.

Example X SAE 30 mineral lubricating oil containing 5% of the product of Example 1, 0.1% of phosphorus as the zinc salt of a mixture of equimolar amounts of di-isopropylphosphorodithioic acid and di-n-decylphosphorodithioic acid, and 2.5% of sulfate ash as a basic barium detergent prepared by carbonating at 150 C. a mixture comprising mineral oil, barium di-dodecylbenzene sulfonate and 1.5 moles of barium hydroxide in the presence of a small amount of water and 0.7 mole of octylphenol las the promoter.

14 Example XI SAE 10W-30' mineral lubricating oil containing 6% of the product of Example 2, 0.075% of phosphorus as zinc di-n-octylphosphorodithioate, and 5% of the barium salt of an acidic composition prepared by the reaction of 1000 parts of polyisobutene having a molecular weight of 60,000 with parts of phosphorus pentasulfide at 200 C. and hydrolyzing the product with steam at 150 C.

Example XII SAE 10 mineral lubricating oil containing 2% of the product of Example 4, 0.075% of phosphorus as the adduct of zinc di-cyclohexylphosphorodithioate treated with 0.3 mole of ethylene oxide, 2% of a sulfurized sperm oil having a sulfur content of 10%, 3.5% of a poly- (alkyl methacrylate) viscosity index improver, 0.02% of a poly-(alkyl methacrylate) pour point depressant, 0.003% of a poly-(alkyl siloxane) anti-foam agent.

Example XIII SAE 10 mineral lubricating oil containing 1.5% of the product of Example 6, 0.075% of phosphorus as the adduct obtained by heating zinc di-nonylphosphorodithioate with 0.25 mole of 1,2-hexene oxide at C., a sulfurized methyl ester of tall oil acid having a sulfur content of 15%, 6% of a polybutene viscosity index improver, 0.005% of a poly-(alkyl methacrylate) anti-foam agent, and 0.5% of lard oil.

Example XIV SAE 20 mineral lubricating oil containing 1.5% of the product of Example 7, 0.5 of di-dodecyl phosphite, 2% of the sulfurized sperm oil having sulfur content of 9%, a basic calcium detergent prepared by carbonating a mixture comprising mineral oil, calcium mahogany sulfonate and 6 moles of calcium hydroxide in the presence of an equi-molar mixture 10% of the mixture) of methyl alcohol and n-butyl alcohol as the promoter at the reflux temperature.

Example XV SAE 10 mineral lubricating oil containing 2% of the product of Example 2, 0.07% of phosphorus as Zinc dioctylphosphorodithioate, 2% of a barium detergent prepared by neutralizing with barium hydroxide the hydrolyzed reaction product of a polypropylene (molecular weight 2000) with 1 mole of phosphorus pentasulfide and 1 mole of sulfur, 3% of a barium sulfonate detergent prepared by carbonating a mineral oil solution of mahogany acid, and a 500% stoichiometrically excess amount of barium hydroxide in the presence of phenol as the promoter at 180 C., 3% of a supplemental ashless detergent prepared by copolymerizing a mixture of 95% (Weight) of decyl-methacrylate and 5% (weight) of diethylaminoethylacrylate.

Example XVI SAE 80 mineral lubricating oil containing 2% of the of phosphorus as zinc di-nhexylphosphorodithioate, 10% of a chlorinated parafiin wax having a chlorine content of 40%, 2% of di-butyl tetrasulfide, 2% of sulfurized dipentene, 0.2% of oleyl amide, 0.003% of an anti-foam agent, 0.02% of a pour point depressant, and 3% of a viscosity index improver.

Example XVII SAE 10 mineral lubricating oil containing 3% of the product of Example 1, 0.075% of phosphorus as the Zinc salt of a phosphorodithioic acid prepared by the reaction of phosphorus pentasulfide with an equimolar mixture of n-butyl alcohol and dodecyl alcohol, 3% of a barium detergent prepared by carbonating a mineral oil solution containing 1 mole of sperm oil, 0.6 mole of octylphenol, 2 moles of barium oxide, and a small amount of Water at C.

1 Example XVIII SAE 20 mineral lubricating oil containing 2% of the product of Example 2 and 0.07% of phosphorus as zinc d-i-n-octyl-phosphorodithioate.

Example XIX SAE 30 mineral lubricating oil containing 3% of the product of Example 7 and 0.1% of phosphorus as zinc di- (isobutylphenyl) -phosphorodithioate.

Example XX SAE 50 mineral lubricating oil containing 2% of the product of Example 7.

Example XXI SAE 90 mineral lubricating oil containing 3% of the product of Example 6 and 0.2% of phosphorus as the reaction product of 4 moles of turpentine with 1 mole of phosphorus pentasulfide.

Example XXII SAE 90 mineral lubricating oil containing 3% of the product of Example 2 and 0.2% of 4,4-bis-methylene- (2,6-di-tert-butylphenol) Example XXIII SAE 30 mineral lubricating oil containing 2% of the product of Example 2 and 0.1% of phosphorus as phenylethyl di-cyclohexylphosphorodithioate.

Example XXIV SAE 90 mineral lubricating oil containing 5% of the product of Example 3 and 1% of the calcium salt of the sulfurized phenol obtained by the reaction of 2 moles of heptylphenol with 1 mole of sulfur.

The above lubricants are merely illustrative and the scope of invention includes the use of all of the additives previously illustrated as well as others within the broad concept of this invention described herein.

The effectiveness of the nitrogenand boron-containing composition as additives in lubricants to impart oxidation-inhibiting, corrosion-inhibiting, and detergent properties is illustrated by the results obtained from an Inhibition-Detergency Test in which 350 cc. sample of a lubricant containing 0.001% of iron naphthenate and 1.5% by weight of the additive to be tested is heated at 300 F. for 48 hours in a 2 x 15 borosilicate tube. A clean copper-lead bearing is immersed in the lubricant along with an SAE 1020 steel test panel. Air is bubbled through the lubricant at the rate of liters per hour. The oxidized sample is allowed to cool to 122 P. whereupon 0.5% (by volume) of water is added and dispersed into the sample. The sample is allowed to stand for hours at room temperature and then filtered through dry No. 1 Whatman paper (double thickness) under slightly reduced pressure. The precipitant is washed with naphtha to constant Weight and reported as milligrams of sludge per 100 ml. of oil. The bearing is scrubbed with naphtha, dried, and weighed, and the bearing weight change is reported in milligrams. The viscosity at 100 F. and 210 F. of the lubricant before and after the test is noted. Thus, the quantity of sludge is an indication of the ability of the additive to prevent the formation of harmful deposits; the bearing weight change is an indication of the corrosiveness of the lubricant; and the viscosity change of the lubricant is an indication of the oxidation resistance of the lubricant. The lubricant base employed in the test is a Mid-continent, conventionally refined mineral oil having a viscosity of about 200 Saybolt Universal Seconds at 100 F. The results of the test are summarized in Table 1 below,

What is claimed is:

1. A lubricating composition comprising a major proportion of a lubricating oil and a minor proportion of an oil-soluble, nitrogenand boron-containing composition prepared by the process comprising forming an acylated nitrogen intermediate by the reaction at a temperature between about C. and 250 C. of one equivalent of a substantially saturated hydrocarbon-substituted succinic acid-producing compound having at least about 50 aliphatic carbon atoms in the substantially hydrocarbon substituent with at least about one-half equivalent of an amido-compound having the formula wherein R is selected from the class consisting of hydrogen and hydrocarbon radicals and R is selected from the class consisting of amino, cyano, carbamyl, and thio' carbamyl, and radicals having the formulas R N-N( R)C (==NR)-, and NC-N (R)O(=R)- and reacting at a temperature between about 50 C. and 250 C. said acylated nitrogen intermediate with a boron compound selected from the class consisting of boron oxide, boron halides, boron acids, ammonium salts of boron acids, and esters of boron acids in an amount to provide from about 0.1 gram-atomic-weight of boron for each mole of said acylated nitrogen intermediate to about 10 gram-atomic-weight of boron for each gramatomic-weight of nitrogen of said acylated nitrogen intermediate.

2. The lubricant of claim 1 wherein the nitrogenand boron-containing composition is prepared by the process comprising forming an acylated nitrogen intermediate by the reaction of a substantially saturated aliphatic olefin polymer-substituted succinic anhydride having at least about 50 aliphatic carbon atoms in the olefin polymer substituent with at least about one-half equivalent of an amido compound having the formula wherein R is a hydrogen radical and R is a guanyl radical and reacting said acylated nitrogen intermediate with boric acid in an amount to provide from about 0.1 gramatomic-weight of boron for each mole of said acylated nitrogen intermediate to about 10 gram-atomic-Weight of boron for each gram-atomic-weight of nitrogen of said acylated nitrogen intermediate.

3. The lubricant of claim 1 wherein the amido compound is cyanoguanidine.

4. The lubricant of claim 1 wherein the nitrogenand boron-containing composition is prepared by a process comprising forming an acrylated nitrogen intermediate by the reaction of a substantially saturated aliphatic olefin polymer substituted succinic anhydric having at least about 50 aliphatic carbon atoms in the olefin polymer substituent with at least about one-half equivalent of an amido compound having the formula wherein R is a hydrogen radical and R is a carbamyl radical and reacting said acylated nitrogen intermediate with 1 7 boric acid in an amount to provide from about 0.1 gramatornic-weight of boron for each mole of said acylated nitrogen intermediate to about 10' gramatomic-weight of boron for each gram-atomic-weight of nitrogen of said acylated nitrogen intermediate.

5. The lubricant of claim 4 wherein the amido compound is urea.

6. The lubricant of claim 1 wherein the nitrogenand boron-containing compositions prepared by the process comprising forming an acylated nitrogen intermediate by the reaction at a temperature between about 80 C. and 250 C. of a polyisobutene substituted succinic anhydride having from about 50 to about 250 carbon atoms in the polyisobutene substituent with about an equivalent amount of cyanoguanidine and reacting said acylated nitrogen intermediate with boric acid in an amount to provide about one gram-atomic-weight of boron for each gramatomic-weight of nitrogen of the acylated nitrogen intermediate at a temperature between about 100 C. and 250 C.

7. The lubricant of claim 1 wherein the nitrogenand boron-containing compositions prepared by the process comprising forming an acylated nitrogen intermediate by the reaction at a temperature between about C. and 250 C. of a polyisobutene substituted succinic anhydride having from about 50 to about 250 carbon atoms in the polyisobutene substituent with about an equivalent amount of ureaand reacting said acylated nitrogen intermediate with boric acid in an amount to provide about one gramatomic-wight of boron for each gram-atomic-Weight of nitrogen of the acylated nitrogen intermediate at a temperature between about C. and 250 C.

References Cited UNITED STATES PATENTS 3,000,916 9/1961 Glass et a1 260-4045 3,018,250 1/ 1962 Anderson et a1. 26032 6.5 X 3,018,291 1/1962' Anderson et a1 260'326.5 3,087,936 4/1963 Le Suer 260-3263 3,254,025 5/1966 Le Suer 252-32] DANIEL E. WYMAN, Primary Examiner. W. H. CANNON, P. P. GARVIN, Assistant Examiners.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3 338 832 Dated August 29 a 1967 William M. Le Suer Inventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 16 line 51 "N-I'q-R' should read H-N-R line 65 "acrylated" should read acylated line 67 "anhydrlc" should read anhydride Signed and sealed this 20th day of April 1971 (SEAL) Attest:

EDWARD M.FLETCHER,JR. WILLIAM E. SCHUYLER, JR. Attestlng Officer Commissioner of Patents 

1. A LUBRICATING COMPOSITION COMPRISING A MAJOR PROPORTION OF A LUBRICATING OIL AND A MINOR PROPORTION OF AN OIL-SOLUBLE, NITROGEN- AND BORON-CONTAINING COMPOSITION PREPARED BY THE PROCESS COMPRISING FORMING AN ACYLATED NITROGEN INTERMEDIATE BY THE REACTION AT A TEMPERATURE BETWEEN ABOUT 80*C. AND 250*C. OF ONE EQUIVALENT OF A SUBSTANTIALLY SATUREATED HYDROCARRBON-SUBSTITUTED SUCCINIC ACID-PRODUCING COMPOUND HAVING AT LEAST ABOUT 50 ALIPHATIC CARBON ATOMS IN THE SUBSTANTIALLY HYDROCARBON SUBSTITUENT WITH AT LEAST ABOUT ONE-HALF EQUIVALENT OF AN AMIDO-COMPOUND HAVING THE FORMULA R-NH-R'' WHEREIN R IS SELECTED FROM THE CLASS CONSISTING OF HYDROGEN AND HYDROCARBON RADICALS AND R'' IS SELECTED FROM THE CLASS CONSISTING OF AMINO, CYANO, CARBAMYL, AND THIOCARBAMYL, AND RADICALS HAVING THE FORMULAS 